Chase Cards:

Hologram Chase Cards

XH1: Wolverine

XH2: Cable

XH3: Gambit

XH4: Magneto

XH5: X-Men

Special Tin Set The tin set feaured a complete set of the basic cards and a Special Power ratings card

Jim Lee Autograph Cards The Jim Lee autograph cards are actually identical to the promotional card se, showing the same discrepancies from the regular cards in the basic set. These signature cards are signed in Silver ink

5-card cello pack A promotional pack of 5 cards was produced with several noticable differences between these and the regular basic set cards. On all 5 cards the trademark and copyright information is printed in a bolder style on the regular card backs. Also the trademark symbol, TM, is printed in black on the promo cards and in red on the regular set.
There are also the following differences on each card:

Cable - Name "Unknown" is printed on promo card vs. name "Unrevealed"on regular card back, different power ratings chart.

Magneto - Name "Unknown" on promo card vs. name "Unrevealed; goes by Magnus" on regular card back, different power ratings chart.

Storm - Different power ratings chart, slightly different text on back.

Wolverine - Text layout is different

X-Men - Text layout is differerent

It is believed that these cards were used for the Autograph cards listed above.

Magneto gold hologram A gold version of the magneto hologram card was created for Advance Comics

Toy Biz variants This card set was used to create a parallel set with the exception that the Toy Biz logo is printed in light grey on the back of the card. These cards were randomly inserted into Toy Biz action figures and there is apparently a Toy Biz variant card for each of the regular set, except for the checklist card.

Comics

X-Fact

In the 1996 limited series, X-men: Brood - Day of Wrath, a woman named Hannah Connover is infected by the Brood Empress, frozen in suspended animation by Iceman and taken by the X-Men to find a cure. She has never been shown on panel since!